Asunto(s)
Drenaje/métodos , Hidrocefalia/enfermería , Ventrículos Cerebrales , Humanos , Hidrocefalia/terapiaRESUMEN
Reading speed and duration were measured for 24 low vision subjects, 12 learning to use closed circuit television and 12 learning to use optical aids. Reading speed and duration increased for both groups during 10 days of training and practice. Improvement occurred by steplike increases and plateaus. Visual acuity was not correlated with either performance measure; reading speed on the initial day of training was correlated with reading speed on the last day. The results have implications for both the prescription of aids and the training of low-vision patients.
Asunto(s)
Ceguera/rehabilitación , Auxiliares Sensoriales , Adulto , Anciano , Humanos , Lentes , Persona de Mediana Edad , Lectura , TelevisiónAsunto(s)
Ceguera , Bastones , Equipo Ortopédico , Auxiliares Sensoriales , Estudios de Evaluación como Asunto , Familia , Estudios de Seguimiento , Humanos , Rayos Láser , Masculino , Persona de Mediana Edad , Viaje , UltrasonidoAsunto(s)
Ataque Isquémico Transitorio/tratamiento farmacológico , Fenoxibenzamina/efectos adversos , Fentolamina/efectos adversos , Animales , Relación Dosis-Respuesta a Droga , Electroencefalografía , Haplorrinos , Hipotensión/inducido químicamente , Inyecciones Espinales , Macaca , Meninges/efectos de los fármacos , Meningitis/inducido químicamente , Fenoxibenzamina/administración & dosificación , Fenoxibenzamina/líquido cefalorraquídeo , Fenoxibenzamina/uso terapéutico , Fentolamina/administración & dosificación , Fentolamina/líquido cefalorraquídeo , Fentolamina/uso terapéutico , Hemorragia Subaracnoidea/complicacionesRESUMEN
DURING MYELOGRAPHY WE OBSERVED THE CONTRAST MATERIAL IN THE SPINAL SUBARACHNOID SPACE WHILE WE CHANGED: (1) the intracranial blood volume by CO(2) inhalation, hyperventilation, and jugular vein compression; (2) the intra-abdominal and intrathoracic pressure by forced expiration with glottis closed; and (3) the CSF volume by withdrawals and reinjections of fluid. The spinal dural sac enlarges with increases in volume of both intracranial blood and CSF. It partially collapses with reductions in volume of both intracranial blood and CSF. With increases in intra-abdominal and intrathoracic pressure, the thoracolumbar sac partially collapses, while the cervical sac enlarges. From these observations we conclude that the spinal dural sac is a dynamic structure, readily changing its capacity in response to prevailing pressure gradients across its walls. It acts as a reservoir for CSF, which moves to and fro through the foramen magnum in response to changes in cerebral blood flow. By its bladder-like ability to alter its capacity, the spinal dural sac provides the `elasticity' of the covering of the central nervous system.